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BACKGROUND AND PURPOSE: In this study on PDR treatment planning of utero-vaginal carcinoma, we analysed the dosimetry of traditional X-ray based plans as it presents on MR images. The potential gain of MRI-based dose optimisation was assessed. PATIENTS AND METHODS: Sixteen patients boosted with PDR brachytherapy after external beam therapy were included. The clinical X-ray based plans were projected on MR images. The GTV, HR-CTV and IR-CTV were retrospectively contoured, as well as the bladder, rectum and sigmoid colon. The dose in the critical organs and target coverage was investigated. In a second phase, the plans were manually optimised using the MR information. The objectives were to lower the dose in the critical organs (85Gy(alphabeta3) for bladder, 75Gy(alphabeta3) for rectum and sigmoid colon) and to increase the HR-CTV dose to D9085Gy(alphabeta10). RESULTS: In the X-ray based plans, D(2cc) in bladder and sigmoid colon exceeded the tolerance doses in 10/16 and 7/16 patients, respectively. Coverage of the IR-CTV with the 60Gy(alphabeta10) was acceptable. D90 of the HR-CTV was below 85Gy(alphabeta10) in 13 out of 16 patients. After optimisation, the dose constraints in the OAR were not exceeded anymore in any patient. The average D(2cc) dose reduction was 7+/-6Gy(alphabeta3) in the bladder and 7+/-4Gy(alphabeta3) in the sigmoid colon for those patients in which the dose constraint was initially exceeded. In addition, an average dose increase of 3Gy(alphabeta10) was accomplished in the HR-CTV. CONCLUSIONS: MRI-based dose optimisation can play an important role to reduce the dose delivered to the critical organs and to improve target coverage.  相似文献   
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PURPOSE: To perform a multicentre intercomparison study of treatment concepts for MRI assisted brachytherapy of cervix cancer based on recommendations of the Gynaecological GEC-ESTRO Working Group. METHODS: Each participating centre (IGR Paris, University Hospital Leuven, Medical University of Vienna) contributed data of one patient with comparable clinical features. GTV, High Risk CTV (HR CTV), Intermediate Risk CTV (IR CTV) and organ walls of bladder, rectum and sigmoid colon were delineated at the time of each brachytherapy fraction on axial MR images with the applicator in place. Dose-volume histograms were calculated to evaluate doses to tumour, target volumes and organs at risk. Dose values were biologically normalised to equivalent doses in 2 Gy fractions (EQD(2), equivalent to 50 cGy/h low dose rate) applying the linear-quadratic model. RESULTS: Total doses to point A from external beam therapy plus brachytherapy ranged from 85 to 91 Gy and were close to the dose covering 90% of HR CTV (D90=85-87 Gy). D90 of IR CTV was within 69-73 Gy. Doses to organs at risk were comparable. CONCLUSIONS: This study indicates the feasibility of the GEC-ESTRO recommendations. Despite different treatment concepts, biologically normalised total doses to tumour, target volumes and organs at risk were comparable.  相似文献   
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We examine whether feeding pregnant and lactating rats hydrogenated fats rich in trans fatty acids modifies the plasma lipid profiles and the expression of adipokines involved with insulin resistance and cardiovascular disease in their 90-day-old offspring. Pregnant and lactating Wistar rats were fed with either a control diet (C group) or one enriched with hydrogenated vegetable fat (T group). Upon weaning, the male pups were sorted into four groups: CC, mothers were receiving C and pups were kept on C; CT, mothers were receiving C and pups were fed with T; TT, mothers were receiving T and pups were kept on T; TC, mothers were receiving T and pups were fed with C. Pups' food intake and body weight were quantified weekly and the pups were killed at day 90 of life by decapitation. Blood and carcass as well as retroperitoneal, epididymal, and subcutaneous white adipose tissues were collected. Food intake and body weight were lower in TC and TT, and metabolic efficiency was reduced in TT. Offspring of TT and TC rats had increased white adipose tissue PAI-1 gene expression. Insulin receptor was higher in TT than other groups. Ingestion of hydrogenated vegetable fat by the mother during gestation and lactation could promote deleterious consequences, even after the withdrawal of the causal factor.  相似文献   
56.
Summary This report deals with the study of longitudinal growth of pre-school children from different socio-economic classes in the urban community of Delhi. The role of socio-economic factors which affect the growth standards of weight, height, circumference of head, chest, arm, calf and pelvic width of these children at different ages from birth up to 5 years is discussed. It is observed that in malnutrition resulting from an adverse effect of poor socio-economic status, all measurements of the body are affected, the height and the head being the least and the weight, the circumferences of the chest, arm and calf the most. From the Longitudinal Morbidity and Mortality Survey of Children’s Unit, Indian Council of Medical Research, New Delhi.  相似文献   
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As part of its evaluation of the Clinical Cancer Education Program (CCEP) at the Albert Einstein College of Medicine, the Office of Educational Research and Evaluation analyzed student performance on neoplastic items of the National Board of Medical Examiners (NBME) Examination Part II. The evaluation provided a successful application of the American Association for Cancer Education (AACE) coding schema for analysis of neoplastic items. Two examinations were analyzed in order to determine the frequency with which specific disease sites, treatment modalities, and question emphasis items appeared. With reference to disease site, the greatest number of questions on both examinations dealt with gynecological issues while the fewest dealt with lung and hematologic-related disease. A breakdown of questions into various treatment modalities indicated that of items that could be categorized, most dealt with surgical treatment, while other therapeutic modalities were given little or no emphasis. Looking at question emphases, the most frequently asked questions referred to diagnostic tests and stratagems, whereas the least amount of emphasis was placed on rehabilitative and psychosocial aspects of the disease. These findings corroborate those reported by Ruckdeschel and his associates and point out several limitations to the content validity of the neoplastic items on NBME Part II.  相似文献   
59.
A prospective, randomized, double-blind study was performed to compare preoperative antibiotic preparation with neomycin (group 1), neomycin and tetracycline (group 2), and placebo (group 3) in patients undergoing elective intestinal surgery. The 196 patients were approximately equally distributed among the three study groups, which proved similar to each other in terms of age, sex, diagnosis, site of lesion, and operative procedure. There were significantly (P < 0.01) fewer patients with postoperative wound sepsis in the neomycin-tetracycline group (group 2) than in either of the two other groups. Postoperative wound infection rates in groups 1 and 3 were nearly identical. Most infections contained both aerobic and anaerobic bacteria. Eight of nine episodes of septicemia due to Bacteroides fragilis occurred in patients in groups 1 and 3.  相似文献   
60.
OBJECTIVE: To evaluate the influence of a twice-weekly progressive resistance training (PRT) program, without a concomitant weight loss diet, on abdominal fat and insulin sensitivity in older men with type 2 diabetes. RESEARCH DESIGN AND METHODS: Nine older men (aged 66.6 +/- 3.1) with type 2 diabetes participated in a 16-week PRT supervised program (50-80% of the one repetition maximum), for all main muscle groups. Basal glycemia, HbA(1c), diet, habitual physical activity, body composition, and upper/lower maximal strength were measured. Insulin sensitivity was determined according to Bergman's minimal model procedure and abdominal fat was obtained by computed tomography. The measurements were taken 4 weeks before training (-4), immediately before training (0), and at 8-week intervals (i.e., weeks 8 and 16) during the 16-week training period. RESULTS: No significant variation was observed in any of the above selected parameters during the 4-week control period. After PRT, both leg and arm maximal strength increased significantly by 17.1 and 18.2%, respectively. Visceral and subcutaneous abdominal fat decreased significantly by 10.3% (from 249.5 +/- 97.9 to 225.6 +/- 96.6 cm(3), P < 0.01) and by 11.2% (from 356.0 +/- 127.5 to 308.6 +/- 118.8 cm(3), P < 0.01), respectively, while no changes were observed in body mass. PRT significantly increased insulin sensitivity by 46.3% (from 2.0 +/- 1.2 to 2.8 +/- 1.6 . 10(4) . min(-1) . muU(-1) . ml(-1), P < 0.01), whereas it significantly decreased (-7.1%, P < 0.05) fasting blood glucose (from 146.6 +/- 28.3 to 135.0 +/- 29.3 mg/dl). Finally, a 15.5% increase in energy intake (from 2,287.1 +/- 354.7 to 2,619.0 +/- 472.1 kcal/day, P < 0.05) was observed. CONCLUSIONS: Two sessions per week of PRT, without a concomitant weight loss diet, significantly improves insulin sensitivity and fasting glycemia and decreases abdominal fat in older men with type 2 diabetes.  相似文献   
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